U.S. patent application number 11/415020 was filed with the patent office on 2007-11-01 for laminates with sound absorbing porperties.
Invention is credited to Glenn E. Cheek.
Application Number | 20070254130 11/415020 |
Document ID | / |
Family ID | 38648667 |
Filed Date | 2007-11-01 |
United States Patent
Application |
20070254130 |
Kind Code |
A1 |
Cheek; Glenn E. |
November 1, 2007 |
Laminates with sound absorbing porperties
Abstract
An automotive carpet with desirable acoustic properties is
formed from a laminate that includes a first layer that includes a
carpet face, a second layer comprising a back coating composition,
a third layer that is formed from polyolefin particles and a fourth
layer that is a foam layer. The laminate can be used as a floor
covering or to make automotive floor mats with desirable sound
absorbing properties and may further include an optional nonwoven
layer to improve the stiffness of the laminate and floor mats
incorporating the laminate.
Inventors: |
Cheek; Glenn E.; (Ringgold,
GA) |
Correspondence
Address: |
SMITH FROHWEIN TEMPEL GREENLEE BLAHA, LLC
Two Ravinia Drive
Suite 700
ATLANTA
GA
30346
US
|
Family ID: |
38648667 |
Appl. No.: |
11/415020 |
Filed: |
May 1, 2006 |
Current U.S.
Class: |
428/95 ;
428/87 |
Current CPC
Class: |
B32B 2605/003 20130101;
B32B 5/22 20130101; B32B 38/12 20130101; Y10T 428/23979 20150401;
B32B 2307/206 20130101; Y10T 428/23921 20150401; B60R 13/083
20130101 |
Class at
Publication: |
428/095 ;
428/087 |
International
Class: |
D05C 17/00 20060101
D05C017/00; B32B 3/02 20060101 B32B003/02; B32B 33/00 20060101
B32B033/00 |
Claims
1. A laminate comprising: a first layer comprising a carpet face, a
second layer comprising a back coating composition, a third layer
comprising a polyolefin, and a fourth layer comprising a foam.
2. The laminate of claim 1 wherein the third layer that comprises a
high density polyethylene and is a porous layer and is formed from
particles of high density polyethylene.
3. The laminate of claim 1 wherein the third layer that comprises
at least about 50 weight percent of high density polyethylene.
4. The laminate of claim 1 wherein the third layer that comprises
at least about 60 weight percent of high density polyethylene.
5. The laminate of claim 1 wherein the third layer that comprises
at least about 70 weight percent of high density polyethylene.
6. The laminate of claim 2 wherein the high density polyethylene
has a density in the range of from about 0.945 grams per cubic
centimeter to about 0.955 grams per cubic centimeter.
7. The laminate of claim 2 wherein the particles of high density
polyethylene have a maximum diameter that is not greater than about
2 millimeters.
8. The laminate of claim 2 wherein the particles of high density
polyethylene have a maximum diameter that is not greater than about
1.7 millimeters.
9. The laminate of claim 2 wherein the particles of high density
polyethylene have a maximum diameter that is not greater than about
1.5 millimeters.
10. The laminate of claim 1 wherein the first layer comprises a
primary backing and bundles of fibers or yarns that are twisted at
a rate of from about 3 to about 5 turns per inch before the bundles
of fibers or yarns are tufted into the primary backing to form the
carpet face.
11. The laminate of claim 1 further comprising a fifth layer that
comprises nonwoven fibers.
12. The laminate of claim 1 further comprising a fifth layer that
comprises a nonwoven fabric that is formed from spunbonded fibers,
spunlaced fibers or a combination thereof.
13. The laminate of claim 1 further comprising a fifth layer
disposed between the first layer and the second layer wherein the
fifth layer comprises nonwoven fibers.
14. The laminate of claim 1 further comprising a fifth layer
disposed between the first layer and the second layer wherein the
fifth layer comprises nonwoven fibers and is adhered to the fourth
layer with an adhesive latex or by flame laminating the fifth layer
to the fourth layer.
15. The laminate of claim 1 wherein the back coating composition
comprises a latex, a copolymer of styrene and butadiene, a
copolymer of ethylene and vinyl acetate or an acrylic polymer.
16. The laminate of claim 1 wherein foam is a polyurethane
foam.
17. A sound absorbing material comprising the laminate of claim
1.
18. A floor mat comprising the laminate of claim 1.
19. An automotive floor mat comprising the laminate of claim 1
20. A floor mat comprising the laminate of claim 1 wherein the
floor mat comprises a periphery and the periphery comprises serging
or binding tape.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to carpet laminates and
particularly carpet laminates that are utilized within automobiles
and other vehicles.
[0003] 2. Description of the Related Art
[0004] Generally, it is considered desirable to reduce the level of
noise within a vehicle passenger compartment. Transmission of
external noises, such as road noise, engine noise, vibrations and
the like into a passenger compartment as well as transmission of
sounds, such as loud music, from within a passenger compartment out
can be reduced through the use of acoustical materials.
Accordingly, sound absorbing and/or deadening materials for
vehicles, in particular luxury automobiles, are used in carpeting,
headliners, seats, dashboards, floor mats, trunk liners,
undercoatings, wheel wells, and under hoods among other areas.
[0005] Carpeting for use within vehicles is conventionally tufted
such as pile or cut and loop or nonwoven. Tufted carpet generally
includes a composite structure in which tufts, or bundles of carpet
fibers are introduced, such as by stitching, into a primary
backing, such as a woven or non-woven fabric. Nonwoven fabric is
composed of fiber that is mechanically entangled by needling, water
jet, or other process. A secondary backing or coating of
thermoplastic material is then applied to the underside of the
carpet construction in order to securely retain the tufted material
in the primary backing. This secondary backing not only
dimensionally stabilizes the construction but can also provide
greater abrasion and wear resistance, and may serve as an adhesive
for an additional layer of material. Carpet laminates may include
or are placed over a pad to provide extra cushioning and sound
absorption.
[0006] In general, the ability of a carpet, more specifically a
carpet laminate, to absorb sound increases as the amount of carpet
or laminate material increases. Unfortunately, increased carpet
material increases the weight as well as the cost of carpet, which
is typically undesirable. Accordingly, there is a need for carpet
materials for use within vehicles that exhibit good sound absorbing
properties and that are also lightweight and low in cost.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention provides a laminate with sound
absorbing properties that includes: a first layer comprising a
carpet face, a second layer comprising a back coating composition,
a third layer comprising a polyolefin, and a fourth layer
comprising a foam. The sound absorbing laminate is useful in
automotive interiors, particularly for making floor mats.
Desirably, the back coating composition is a latex, a copolymer of
styrene and butadiene, a copolymer of ethylene and vinyl acetate or
an acrylic polymer and the fourth layer is a foam, preferably a
polyurethane foam.
[0008] In certain embodiments, the third layer comprises a high
density polyethylene and is a porous layer and is formed from
particles of high density polyethylene. In certain more desirable
embodiments, the third layer comprises at least about 50 weight
percent of high density polyethylene, at least about 60 weight
percent of high density polyethylene and even at least about 70
weight percent of high density polyethylene. Desirably, the high
density polyethylene has a density in the range of from about 0.945
grams per cubic centimeter to about 0.955 grams per cubic
centimeter.
[0009] In certain embodiments the particles of high density
polyethylene that are used to from the third layer have a maximum
diameter that is not greater than about 2 millimeters, not greater
than about 1.7 millimeters and in some embodiments not greater than
about 1.5 millimeters. The first layer may include a primary
backing and bundles of fibers or yarns that are twisted at a rate
of from about 3 to about 5 turns per inch before the bundles of
fibers or yarns are tufted into the primary backing to form the
carpet face. The laminate may also include an optional fifth layer
between the fourth and the third layers that is a nonwoven fabric.
The nonwoven fabric may be formed from spunbonded fibers, spunlaced
fibers or a combination thereof. The fifth layer of nonwoven fibers
may be adhered to the fourth layer with an adhesive or by flame
laminating the fifth layer to the fourth layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] A full and enabling disclosure of the present invention,
including the best mode thereof is set forth in the detailed
description which makes reference to the appended figures in
which:
[0011] FIG. 1 is a perspective view of an automotive floor mat,
[0012] FIG. 2 is an enlarged, cross-sectional view of a first
exemplary carpet laminate of the present invention having a loop
pile surface;
[0013] FIG. 3 is an enlarged, cross-sectional view of another
exemplary carpet laminate of the present invention having a cut
pile surface;
[0014] FIG. 4 is an enlarged, detailed view of the carpet laminate
of FIG. 3;
[0015] FIG. 5 is an enlarged, cross-sectional view of a yet another
exemplary laminate of the present invention; and
[0016] FIG. 6 is an enlarged, detailed view of carpet laminate or
FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The drawings and detailed description provide a full and
detailed written description of the invention, and of the manner
and process of making and using it, so as to enable one skilled in
the pertinent art to make and use it, as well as the best mode of
carrying out the invention. The detailed description uses numerical
and letter designations to refer to features in the drawings. Like
or similar designations in the drawings and description have been
used to refer to like or similar parts of the invention. The
examples set forth in the drawings and detailed description are
provided by way of explanation of the invention and are not meant
as limitations of the invention. The present invention thus
includes any modifications and variations of the following examples
as come within the scope of the appended claims and their
equivalents.
[0018] The present invention is primarily concerned with laminates
that have acoustical properties that can be used as floor coverings
and more particularly floor mats in automobiles. However, the
laminates of the present invention may find use in other areas
within a vehicle as well as sound absorbing materials for use in
other structures, including but not limited to buildings. In a
first exemplary embodiment, the present invention provides a
laminate with acoustical properties that includes: a first, carpet
facing layer; a second, layer formed from a back coating
composition, a third porous layer that is formed from polyolefin
particles; and a fourth, base layer that is formed from a
polyurethane foam. Laminates of the present invention can be used
to make automotive floor mats, an example of which is illustrated
in perspective in FIG. 1 as floor mat 400 having a looped carpet
surface 12A.
[0019] Referring now to the drawings, and to those embodiments of
the invention here presented by way of illustration, FIG. 2 shows a
cross section of an automotive carpet that is a laminate generally
designated 100. The exemplary laminate 100 illustrated in FIG. 2
includes a carpet facing layer 10 having a loop pile facing layer
10A that includes face yarns 12 and a primary backing generally
designated 14. The first, carpet facing layer 10A forms the
uppermost surface of the laminate 100 of the illustrated
embodiments and may be any type surface that is used for carpet
surfaces. The carpet facing layer 10 may have a pile cut surface
12B as illustrated in FIG.3, a loop surface 12A as illustrated in
FIG. 2 or a combination of cut and loop fibers (not illustrated)
and can be formed from any type of yarns or fibers that are used to
make carpet surfaces including, but not limited to, polyolefin
yarns, polyamide (commonly referred to as nylon) yarns and
polyester yarns and so forth.
[0020] The bundles of fibers or yarns 12 that form the carpet
surface 12A or 12B are tufted through a primary backing 14 as is
known in the art. In the certain desirable embodiments, the bundles
of fibers or yarns 12 are twisted a rate of about 2 turns per inch
to about 6 turns per inch, more preferably from about 3 to about 5
turns per inch and in an exemplary embodiment, the fibers are
twisted 4 and a half turns per inch before the bundles of fibers or
yarns 12 are tufted through primary backing 14 to form a random
loop or a cut pile pattern. In certain embodiments, the bundles of
fibers or yarns 12 do are not twisted before tufting. Suggested
primary backing materials include, but are not limited to, jute
woven backings, woven polypropylene backings, nonwoven polyester
backings, nonwoven polyamide backings and other woven and nonwoven
backings and the like. In certain desirable embodiments, the
primary backing is a jute woven backing or a nylon nonwoven backing
or a polyester nonwoven backing, for example a polyethylene
terephthalate (PET) nonwoven fabric. Commercial examples of
suggested nonwoven backings include, but are not limited to,
Colback.RTM. thermally bonded spunlaid nonwoven fabric that is made
from bi-component filament with a polyester core and a polyamide
(nylon 6) skin available from Colbond, Inc, of Enka, N.C. and
LUTRADUR.RTM. nonwoven fabric that is a PET nonwoven fabric that is
marketed as a tufted-carpet carrier by Freudenberg Nonwovens of
Durham, N.C. Suggested woven jute backings have a basis weight of
from about 8 to about 10 ounces per square yard. And, suggested
basis weights nonwoven moldable primary backings have basis weights
that range from about 100 grams per square meter (about 2.9 ounces
per square yard) to about 120 grams per square meter (about 3.5
ounces per square yard).
[0021] To minimize the loss of fibers and tufts, a layer 20 of back
coating composition can be applied to underside of the primary
backing 14. A back coating can be used to lock in the back stitches
of the carpet and improve wearability of the carpet laminate. By
way of nonlimiting example, the back coating composition may be or
include a latex such as natural latex, a copolymer of styrene and
butadiene such as a styrene butadiene rubber (SBR), a copolymer of
ethylene and vinyl acetate (EVA) or a polymer or an acrylate
referred to generally as an acrylic, or any combination or
variation thereof. Suggested commercially available, back coating
compositions include, but are not limited to, styrene butadiene
rubbers and modifications thereof.
[0022] A third, porous layer 30 preferably formed from particles of
a polyolefin, such as polypropylene and more preferably
polyethylene, or a mixture of polyolefins is applied to the back
coated surface of the tufted primary backing. For example, a porous
layer of polyolefin can be formed by depositing from about 2 to
about 20 ounces of polyolefin particles per square yard of carpet
on to the backing of the carpet with the use of a powder coater.
More preferably from about 6 to about 12 ounces of polyolefin per
square yard and even more preferably from about 8 to about 12
ounces per square yard is powder coated to the back coated surface
of the tufted carpet. Desirably, the maximum size of the particles
of polyolefin is selected by screening. Suggested polyolefin
particles include polyethylene and polypropylene particles that
have a maximum diameter (or maximum dimension) that is not greater
than about 2 millimeters (mm) and more preferably not greater than
about 1.7 mm and still more preferably have a maximum diameter that
is not greater than about 1.5 mm. Desirably, the particles have an
average maximum dimension that is about 1 mm. In the exemplary
embodiment, polyolefin pellets were ground and then sifted through
an ASTM E-11 size no 12 mesh screen to obtain smaller polyolefin
particles for forming a laminate of the present invention. The
particles are preferably thermofusible and can be deposited,
dispensed or otherwise applied onto a backing as particles and then
heated with for example an infrared lamp so that particles will
coalesce, sinter or fuse together to form a porous but rigid layer
of polyolefin. The thickness of the layer can and will vary across
the width and length of the laminate.
[0023] It is suggested that the polyolefin particles include high
density polyethylene (HDPE) particles or polypropylene particles to
increase stiffness. The polypropylene may be or include recycled
polypropylene, for example polypropylene particles that are
obtained from recycled milk containers. As stated, including
polyethylene particles with higher the density, specifically HDPE,
increases the stiffness of the overall carpet laminate 100. High
density polyethylenes (HDPEs) have a density of greater than or
equal to 0.941 grams per cubic centimeter (g/cc) and particularly
suggested high density polyethylenes have a density in the range of
from about 0.945 to about 0.955 g/cc. The particles that can be
used to form layer 30 may include a mixture of polyolefin particles
and in one suggested embodiment include a mixture of HDPE and low
density polyethylene (LDPE) particles. Low density polyethylenes
have a density in the range of from about 0.910 to about 0.940 g/cc
and suggested low density polyethylenes have a density in the range
of from about 0.910 to about 0.917 g/cc. Generally, HDPEs have less
branching and greater tensile strength than LDPEs but may require
higher processing temperatures, for example melting
temperature.
[0024] In an exemplary embodiment, layer 30 is formed from a
mixture of about 75 weight percent of HDPE particles and about 25
weight percent of LDPE particles. Desirably, the layer 30 acts as a
moisture barrier but is air permeable to absorb sound. In exemplary
embodiments, layer 30 is formed by depositing polyethylene
particles onto a latex back coating that has been applied to the
back side of the carpet and then heating the polyethylene particles
to form a porous layer. The porous layer of polyethylene may be
continuous or discontinuous and should not be melt extruded. Melt
extruded polyethylene layers are not considered porous and do not
have desirable sound absorbing properties. The layer formed from
the polyolefin particles varies in thickness throughout the
laminate and typically may vary from about 2 microns in thickness
to about 1 millimeter in thickness. The polyolefin layer may allow
the laminate to be hot molded into non-planar, three-dimensional
contours and provides stiffness to the laminate. The stiffness of
the layer and the laminate can be varied by the relative amounts of
HDPE, LDPE and/or polypropylene used in layer 30.
[0025] A base layer 40 is contacted to layer 30 after layer is
heated, for example with an infrared lamp, to form the bottom
surface of the laminate 100. The laminate 100 can then be passed to
a chill roll to cool and fix the laminate. Layer 40 is preferably a
foam layer that is formed from polyurethane or a polymer of a
urethane or a mixture of urethanes and may be a polyester- or a
polyether-polyurethane foam. Preferably, the base layer 40 is a
layer of an open cell foam and has a thickness that ranges from
about 1/8 of an inch to about 1/4 of an inch. Suggested densities
for the base layer 40 range from about 1 pound per cubic foot to
about 2 pounds per cubic foot and more preferably from about 1.2 to
about 1.8 pounds per cubic foot. Desirably, the polyurethane foam
layer is air permeable relative to rubber, vinyl, thermoplastic
olefin (TPO) and other impermeable layers used in conventional
automobile floor mats. Desirably, the foam layer will have a high
coefficient of friction to prevent an automotive floor mat from
sliding. Such floor mats will have decrease weight and not require
the use of spikes, protrusions or other features used in
conventional automotive floor mats to keep the floor mat from
moving during use.
[0026] In a second exemplary embodiment, the present invention
provides a laminate that further includes an optional, fifth layer
50 of nonwoven fibers. In the embodiment illustrated in FIG. 4 and
in greater detail in FIG. 5, optional nonwoven layer 50 is located
between the base foam layer 40 and polyolefin layer 30 of the
laminate. As used herein, nonwoven layer includes, but is not
limited to, a spunbonded layer, a spunlaced layer, or a needle felt
layer and laminates thereof and may include nonwoven layers that
include spunbonded fibers, spunlaced fibers and combinations of
fibers that include spunbonded and/or spunlaced fibers. Suggested
nonwoven spunbonded fabrics and nonwoven spunlaced fabrics can be
formed from polyesters such a polyethylene terephthalate (PET),
polypropylene spunbonded fibers, polypropylene spunlaced fibers,
and blends of PET and nylon (polyamides). One suggested nonwoven
layer that can be used as an optional layer 50 is a spunbonded,
polypropylene nonwoven that was obtained from Freudenberg Nonwovens
of Durham, N.C. under the trade name EVOLON.RTM.. Suggested
nonwoven fabrics for layer 50 can have a basis weight within the
range of from about 2 osy to about 20 osy and preferably have a
basis weight in the range of from about 10 to about 15 osy.
[0027] The illustrated, exemplary laminates 100 were made by a
process of manufacture as follows. A textile carpet 10 having a
back surface 14 was obtained in roll form. A layer of latex coating
was applied to the back surface of the carpet at a rate of about 7
ounces of latex per square yard of carpet. Next, polyethylene
particles were deposited over the latex back coating. The
polyethylene particles were applied to the coated carpet at a
density of about 6 to about 7 ounces per square yard of carpet and
then heated with an infrared lamp. Next a layer of polyurethane
foam obtained from a roll is contacted to the heated back surface
of the carpet coated with polyethylene and pressure was applied to
attach the foam backing to the coated back surface of the carpet.
The laminate including the foam layer were then passed through a
chill roll with pressure to form a sound-absorbing, unitary carpet
laminate 100.
[0028] In an alternative embodiment, the foam layer 40 is flame
laminated to layer 30 or optional nonwoven layer 50 by flame
heating lamination. For example, a flame may be used to melt a
surface of the foam layer which can then be contacted to the layer
30 or optional layer 50 of the laminate and then cooled to weld
layer 40 to layer 30 or layer 50. As previously stated, optional
layer 50 may be a spunbonded nonwoven fabric, needle felt nonwoven
fabric or a spunlaced nonwoven fabric. The unitary carpet structure
may be cut to size for hot molding to a desired shape as is known
in the art. In certain embodiments, the sound-absorbing carpet
laminate of the present invention is cut and shaped into mats that
are designed and adapted to be placed on the carpet surface of
automobiles. The mats may include serging or binding tapes 60 at
the perimeters of the mats to provide finished edges and/or to
protect the edges of the mats.
[0029] Laminate materials of the present invention can have
beneficial sound absorbing and/or deadening properties as well as
reduced weight. The laminate materials of the present invention are
believed to absorb and/or deaden sound by allowing sound to be
transmitted through the laminate and deadened as opposed to
reflecting or otherwise transmitting sound. Thus, laminates of the
present invention are desirable for use as interior coverings in
automobiles and to make automotive floor mats. The floor mats can
be original equipment that is sold with the automobile or can be
sold as aftermarket, replacement floor mats and carpets. Although
the present invention has been primarily described with respect to
laminates can be used as floor coverings and floor mats, laminates
of the present invention may find use in other areas within a
vehicle as well as sound absorbing materials for use in other
structures including, but not limited to, commercial and
residential buildings.
[0030] While the present invention has been described in connection
with certain preferred embodiments, it is to be understood that the
subject matter encompassed by way of the present invention is not
to be limited to those specific embodiments. On the contrary, it is
intended for the subject matter of the invention to include all
alternatives, modifications and equivalents as can be included
within the spirit and scope of the following claims.
* * * * *